Low vaccination rates have been blamed for a spike in whooping cough cases between Coffs Harbour and Tweed Heads.
Health authorities say 150 cases have been reported just this year.
North coast’s public health director Paul Corben told ABC radio that the number of cases was twice the state average over a five-year period.
Mr Corben said there were half the number of cases of whooping cough in Ballina Shire where vaccination rates were higher than neighbouring Byron Shire, where they were lower.
He said that people vaccinated against the disease as children should get a booster shot.